The present application is based on Japanese Patent Application No. 2000-284516, which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to the opening and closing apparatus for the opening and closing member of a vehicle which is arranged such that the opening and closing member of the vehicle such as a back door, tail gate or the like is opened and closed by a motor drive.
2. Description of Related Art
In a conventional opening and closing apparatus, as shown in Japanese Utility Model Publication No. 06-71852U, there is an opening and closing apparatus which is arranged such that on a roof of a vehicle body, there is disposed a drive mechanism including a motor, a speed reduction device linked to the motor, a segment gear, which is horizontally rockable, engaging a pinion which is the output axis of the speed reduction device, and a rod having the front end portion pivotally secured to the segment gear and having the rear end portion connected to a door, and that the rod is moved back and forth by the rocking motion of the segment gear, thereby opening and closing the door.
In the conventional opening and closing apparatus as described above, however, the front end portion of the rod is connected to the segment gear using a ball joint etc. so that the rod can be vertically slantingly moved around its front end portion accompanying the opening and closing operation of the door, and hence the connection of the drive mechanism with the door becomes complicated, thus involving a cost overrun.
Also, since the segment gear is largely rocked along the roof surface, the attachment space for the drive mechanism must be made large, and accordingly the overhead clearance of a rear seat occupant is reduced.
In view of such problems as described above which the conventional art possesses, the invention has an object to provide the opening and closing apparatus for the opening and closing member of the vehicle which is arranged such that the drive mechanism body fixed to the vehicle body and the opening and closing member can be connected in a simple arrangement, thereby attaining a cost reduction, and moreover the attachment space for the drive mechanism body is reduced, thereby achieving the enlargement of an interior space.
According to the invention, the above problems are solved in the following manners.
(1) In the opening and closing apparatus for the opening and closing member of the vehicle which is arranged such that the opening and closing member pivotally supported on the vehicle body with a transversely directed hinge axis so as to be openable and closeable is opened and closed by the driving force of a motor, the pinion pivotally mounted on the vehicle body by the axis parallel to the hinge axis is arranged to be rotated in forward and reverse directions by the motor provided on the vehicle body, the rack engaging the pinion is provided on the edge of the rack rod having one end portion pivotally secured by a transversely directed axis on the portion separated from the hinge axis of the opening and closing member, and in a partial portion of the vehicle body slightly spaced from the pinion, there is provided the guide member which slidably engages the longitudinal guide groove provided on the rack rod and supports the rack rod so as to be rotatable about the axis parallel to the axis of the pinion.
(2) In the above opening and closing apparatus, the guide member may be pivotally mounted on the vehicle body by a transversely directed axis.
(3) Further, the guide groove may be provided on one side surface of the rack rod in the form of a U-shape in cross section, and the guide member is formed by the roller which rolls and slides along the upper and lower opposite surfaces of the guide groove.
(4) Furthermore, either side surface of the rack rod may be clamped by the retaining member provided on the vehicle body.
(5) Furthermore, the guide member may be provided on the opposite surface of the retaining member from one side surface of the rack rod.
(6) In the above opening and closing apparatus, a partial portion or an entire portion of the rack and guide groove may be shaped in a substantially arc-shape having a center of curvature on the pinion side.
(7) Further in the above opening and closing apparatus, the distance between the pitch line of the rack and the center line of the guide groove maybe changed along the longitudinal direction of the rack rod such that the tilt angle of the rack rod with respect to the straight line connecting the axle center of the pinion with the center of the guide member becomes less, the farther separated from a right angle.